Here's how to help the Souls of Purgatory. Maria Simma tells us

1) Especially with the sacrifice of the Mass, which nothing could make up for.

2) With expiatory sufferings: any physical or moral suffering offered to souls.

3) after the Holy Sacrifice of the Mass, the Rosary is the most effective means of helping the souls in purgatory. It brings them great relief. Every day many souls are freed through the Rosary, otherwise they would have had to suffer many more years.

4) The Via Crucis can also bring them great relief.

5) Indulgences are of immense value, souls say. They are an appropriation of the satisfaction offered by Jesus Christ to God, His Father. Anyone who during the earthly life gains many indulgences for the deceased will also receive, more than others in the last hour, the grace to fully gain the plenary indulgence granted to every Christian in "articulo mortis". It is a cruelty not to put to profit these treasures of the Church for the souls of the dead. Let's see! If you were in front of a mountain full of gold coins and had the opportunity to take at will to help poor people unable to take them, wouldn't it be cruel to refuse them this service? In many places the use of indulgent prayers decreases year by year, and so also in our regions. The faithful should be exhorted more to this practice of devotion.

6) Alms and good works, especially gifts in favor of the Missions, help the souls in purgatory.

7) The burning of the candles helps the souls: first because this loving attention gives them moral help then because the candles are blessed and illuminate the darkness in which the souls find themselves.
An eleven year old boy from Kaiser asked Maria Simma to pray for him. He was in purgatory to have, on the day of the dead, blown out the candles burning in the graves at the cemetery and to have stolen the wax for fun. Blessed candles have a lot of value for souls. On the day of Candlemas Maria Simma had to light two candles for one soul while enduring for it expiatory sufferings.

8) The throwing of blessed water mitigates the pains of the dead. One day, passing by, Maria Simma threw water blessed for souls. A voice said to her: "Again!".
All means do not help souls in the same way. If during his life someone has little esteem for Mass, he will not take advantage of it when he is in purgatory. If someone has had a heart failure during their lifetime, they receive little help.

Those who sinned by defaming others must hardly atone for their sin. But anyone who has had a good heart alive receives a lot of help.
A soul who had neglected to attend Mass was able to ask for eight Masses for his relief, since during his mortal life he had eight Masses celebrated for a soul of purgatory.